Improvement in wood-screws



J. A. BIDWELL.

WOOD SCREW.

No. 42,905. P atented May 24, 1864.

UNITED STATES PATENT O FICE.

JASON BIDWELL, OF BOSTON, MASSACHUSETTS, ASSIGNOR TO HIMSELF, A. CHURCHILL, H. T. LITOHFIELD, AND DANIEL M, ROBERTSON.

IMPROVEMENT IN WOOD-SCREWS.

Specification forming part of Letters Patent No. 42,995, dated May 24, 1864.

To all whom it may concern.- Be it known that I, J ASON A. BiDwELL, of the city of Boston, in the county of Sutfolk andState of Massachusetts, haveinvented certain new and useful Improvements in Vood- Screws; and I do herebydeclarc that the same are described and represented in the following specification and drawings.

To enable others skilled in the art to make and use my improvements, I will proceed to ,.describe their construction and use, referring to the drawings, in which the same letters in-. dicate like parts in each of the figures.

Figure 1 is an elevation of a screw with my improvements.

The nature of my invention and improvements inv woodscrews consists in a \/-shaped or angularedged thread, with a score between the threads with a semicircular-shaped. bottom, also, in combining therewith a tapering or conical point.

In the accompanying drawings, A is the stem of the screws ;-B,the head, and 0 the Fig. 2 is a section of Fig. 1.

are broken by the old fashioned thread with a.

' the wood in such a manner that itwill hold nearly or quite as much as when screwed into the wood at a right angle to the grain of the wood.

I believe I have described and represented my improvements in wood-screws so as to en able any person skilled. in the art to make and use them without further invention or experiment.

I will now state what I desire to secure by Letters Patent, to wit:

As anew article of manufacture, the woodscrew described-to wit, a wood-screw with a stem of uniform size, (except the tapering point,) and made with a-taperin-g point, sharpedged thread, and concave score,-all as above described.

' JASON A. BIDWEIJL. Witnesses:

- ANTHONY MARTIN.

A. W. BOARDMAN. 

